For example, in a recording technique for an optical recording medium such as a DVD (Digital Versatile Disc) or a BD (Blu-ray Disc: registered trademark), as it is known as so-called write strategy, it is known that adjustment of a laser driving pulse for recording is performed.
In recent years, a technique for executing such write strategy adjustment for each of inserted disks is used.
For example, Japanese Patent No. 4274183 (Patent Document 1) proposes a technique for applying trial writing under q+1 conditions to the number (q) of edge types desired to be adjusted, learning the behavior of the edge types, and obtaining, on the basis of a result of the learning, through a calculation, an optimum edge shift amount for each of the edge types desired to be adjusted.
JP-A-2008-47181 (Patent Document 2) discloses, as a technique for measuring shift amounts of mark edge positions that should be used as evaluation values of the write strategy adjustment, a technique for making it possible to accurately measure shift amounts of edge positions concerning a short mark such as 2T (T represents channel bits) even when intersymbol interference occurs in a high-density optical disk such as a BD.